Merlin Season 3 Episode 2

The Great Dragon returns Merlin to Camelot,where he convinces Gaius of Morgana's treachery and they break the curse on Pendragon by burning the mandrake doll. Nonetheless they feel that he would not believe them if they exposed her and,whilst Cenred's men lay siege to the castle, Morgana,using a rowan wood magic staff,creates an army of sword-wielding skeletons by magic to fight the knights inside Camelot. Merlin destroys the staff and the skeletons disintegrate and,as the tide turns in favour of Camelot,Cenred calls off the siege. Morgana,however,takes the credit for destroying the spell and is acclaimed by her foolish guardian.